Originally Posted by
themaster24
Blizz has set that precedent, though. That's how it's been for some time. You didn't have to go back to the broken shore to grind out rep in order to unlock an extra Relic slot. Nazjatar is old content, Mechagon overworld is old content, EP is old content. Some of the essences from those sources are BiS for a variety of specs. It's also not like we're just talking about doing a relatively short, old story line (i.e. unlocking Concordance, 3rd relic slot). It's grinding stuff that by Blizz's own standards should not be necessary to grind to get relevant power for the patch.
Obviously, not all the essences added in 8.2 are locked behind old content. Op:Mechagon is still current content, Islands, M+, PvP. Those essences are provided by sources players will always be doing.